The change in focal length of an eye lens is caused by the action of the : (a) pupil (b) retina. (c) ciliary muscles. (d) iris.

The human eye forms the image of an object at its : (a) cornea (b) iris (c) pupil (d) retina

The human eye can focus on objects at different distances by adjusting the focal length of the eye lens. This is due to : (a) presbyopia (b) accommodation (c) near-sightedness (d) far-sightedness

A student has difficulty reading the blackboard while sitting in the last row. What could be the defect the child is suffering from? How can it be corrected?

What is the far point and near point of the human eye with normal vision?

A person with a myopic eye cannot see objects beyond 1.2 m distinctly. What should be the type of the corrective lens used to restore proper vision?